I'm new to both this synths and this forum - another reformed guitar player with too many pedals.

Anyways, I've got an ARP Solus and just bought an Arturia Minibrute to, hopefully, connect together in glorious harmony. Unfortunately, when I connect the pitch and gate outs from the Minibrute to the ARP, the ARP's octaves are way too high and out of tune. I did a little research and saw that voltages need to be changed in some way, but I can't find concrete info on what exactly needs to happen. Does anybody have any clue?

Last edited by Cotillion on Wed Mar 13, 2013 12:49 am, edited 1 time in total.

If you are going to run the ARP from the MB the ARP must be properly calibrated, because even if the ARP's VCO's are scaled correctly with the ARP's keyboard if the ARP keyboard CV is not also exactly calibrated to 1V/octave the synth won't play in tune with the Arturia.

Have you tried simply pulling the ARP's master tune slider right down to see if you can get it close to the correct range when played with the MB?

Synthesizer service tech since 1982.Synth parts and service, Sydney Australia.

Cotillion wrote:Yeah, I've messed with the master tune. It still plays 3 or 4 octaves higher and not at the same pitch

Is it possible to switch the MB octave down? If you have a multimeter put it across the tip and sleeve of the lead that you have coming out of the MB's CV out jack and measure the voltage while you play the bottom key on the MB and see what voltage is produced. Sounds like it must be set fairly high, I wouldn't have thought that it should be more than about 3V to put the MB's little keyboard in a reasonable octave range...

Synthesizer service tech since 1982.Synth parts and service, Sydney Australia.

I had a similar problem when using the Moog FreqBox as a second oscillator expander. It wouldn't play in tune when cv-ed to the Minibrute and it was pitched higher by an octave even at the lowest frequency setting on the FB vco. Luckily I also have a Moog CP-251 which features a cv mixer with offset and two attenuators. The offset is the most important and I can now tune the MB keyboard cv pitch output over several octaves now. It's also proving useful when interfacing with my Lil Phatty - it too is pitched an octave off.

I know they're pricey - but it would be a definite solution and it's very useful tool too. Apart from the four way mixer (with + and - outputs. hello reverse keyboard scaling!) and attenuators, there's a cv controllable LFO, extra noise source, lag generator, four way multiple and sample & hold.

“I have stretched ropes from steeple to steeple; garlands from window to window; golden chains from star to star, and I dance.” - Rimbaud

I use my Minibrute to play my modular synth with the CV/Gate outputs (using the 1v/oct input on each modular VCO), so it's sending out usual 1V/Octave voltages at least. Might be that your ARP has a different scaling though.

1V per octave means that there is 12 specific voltages(corresponding to notes, 12 notes in an octave) between 1-2 volts. It became the standard after a while, but early synths had different ranges, probably just to be uncompatible with their competitors.